1. Field of the Invention
The present invention relates to a film deposition apparatus.
2. Description of the Related Art
Atomic Layer Deposition (ALD) is known as a method of forming a thin film such as a silicon oxide film (SfO2) on a substrate such as a semiconductor wafer (simply referred to as a “wafer” hereinafter). By ALD, plural kinds of process gasses (reaction gasses) which react with each other are supplied in order onto a substrate to form a film as a reaction product.
Patent Document 1 and Patent Document 2 disclose a film deposition apparatus that performs ALD. In such a film deposition apparatus, plural substrates are placed on a turntable, which is provided in a vacuum chamber, in the circumferential direction. Then, a first process gas and a second process gas are respectively supplied from a first process gas nozzle and a second process gas nozzle onto the substrates in order while rotating the turntable. Here, a first processing area and a second processing area are provided below the first process gas nozzle and the second process gas nozzle, respectively. Further, separation areas are provided between the first processing area and the second processing area by flowing separation gas. Further, gas evacuation ports are respectively provided for the first processing area and the second processing area at a circumference of the turntable for evacuating gasses in the vacuum chamber.
In the first processing area and the second processing area, the first process gas and the second process gas flow toward the gas evacuation ports with the separation gas, respectively. With this structure, mixing of the first process gas and the second process gas can be suppressed.
In Patent Document 3, an apparatus in which plural wafers are placed in the circumferential direction on a horizontal table, which is capable of being rotated, is disclosed. In the apparatus, a gas evacuating pipe is provided at a periphery of a gas supplying pipe to evacuate a carrier gas and an excess reaction gas from the gas evacuating pipe.
Present inventors have been further examining a structure by which a film with a high in-plane uniformity is formed.